In the past, a wide variety of systems have been developed for automatically handling lumber from the time a log enters a lumber mill until the time rough or finished boards leave the mill. More specifically, a wide variety of systems have been developed for automatically moving boards from one milling operation to the next starting from the time a log enters a mill and ending when rough (or finished) boards leave the mill. Many such systems include provisions for grading boards after they have been milled to size, prior to the boards leaving the mill. In most systems that provide for lumber grading, a trained person views uniform size boards and determines their grade. The resulting grade information may be used to collate boards of the same size, either manually or automatically. After the boards are collated according to grade and size, grade and size information is applied, usually by hand, to the boards.
While prior art systems of the type generally described above are useful when the boards are uniform in dimension and collated by grade prior to marking, such systems are not useful in situations where the boards are of nonuniform size and grade, whereby each board must have its grade and size separately determined and, then, each board must be separately marked. In this regard, boards of nonuniform grade and size are usually obtained from trees that are scarce, yet have highly desirable wood, such as walnut, oak, etc. It is the desire to obtain the maximum amount of wood from such trees that result in their being milled into nonuniformly sized boards. Furniture lumber is frequently produced in such a manner. The only sizing of such lumber is the cutting of random length rough cut boards to fixed lengths using a trimming saw system. The trimming saw system includes a plurality of positionable trimming saws each having a cutting plane lying parallel to the direction of movement of a conveyor moving the boards. The trimming saws may be mounted above or below the conveyor and are independently movable into a position suitable for cutting the moving boards to length. Which saw is positioned for cutting is either manually determined by an operator or, in some systems, automatically determined by a control system that obtains data about the boards from sensors mounted transverse to the direction of board movement, upstream of the position of the trimming saws. The control system uses the sensed length information to control the saws and, thus, the ultimate length of the boards in step increments.
Regardless of how lumber is milled, or data, such as grade, length, width and thickness, is determined, it is often necessary to encode certain lumber information onto the board. If this is required for each board, the data must be accumulated on a board-by-board basis. Obviously, the manual collation of this information and, then, the manual application of the resulting data to each board is time consuming and, thus, costly. As a result, it would be desirable to provide a system for automatically collating such information and, then, automatically marking the information on each board of a series of boards.
Therefore, it is an object of this invention to provide a system for automatically accumulating and collating selected data about boards.
It is another object of this invention to provide a system for automatically accumulating and collating selected data about boards and applying a related code to the boards.
It is also an object of this invention to provide a system for automatically accumulating and collating selected data about random length boards and applying a related code to the boards on a piece-by-piece basis.
It is a further object of this invention to provide a lumber marking system for automatically determined information about the volume of boards and collating this information with information about the grade of the boards and controlling a lumber marking mechanism for marking a related code on the edge of each board.
One of the reasons why the prior art has failed to provide a suitable system for automatically collating information about boards on a piece-by-piece basis and applying a suitable code to each board, results from the lack of a suitable mechanism for applying code marks to the boards. In this regard, uniformly, prior art lumber marking mechanisms are manually adjustable. In such marking mechanisms each time a new code is to be applied, the marking mechanism must be manually set to the new code. The disadvantage of such devices is, of course, the requirement that system operation be stopped each time a new code is to be applied. System shutdown is particularly time consuming and, thus, expensive in environments where a different code may have to be applied to each board. Previously this disadvantage has been prevalent both with print type marking devices and embossing type marking devices.
Consequently, it is also an object of this invention to provide a new and improved marking apparatus that is readily controlled by a control system such that each board in a series can be marked on a piece-by-piece basis, without system shutdown.
It is a further object of this invention to provide a new and improved embossing mechanism that is readily controllable by a control system such that a different code can be embossed into the edge of boards on a piece-by-piece basis without system shutdown.